1. Field of the Invention
The present invention relates generally to an Internet broadcasting system supporting a broadcast service using Internet Protocol (IP), i.e., an Internet data transmission protocol (e.g., an IPTV service), and in particular, to a method for sharing an item (hereinafter referred to as bookmark) indicating a specific point of contents or a service represented by protocol interworking between various devices present in a home network with other IPTV broadcast service users.
2. Description of the Related Art
In the current IP-based convergence era, the convergence of communication and broadcast services is being touted as a highly marketable next-generation new business model and one of the next-generation market-leading technologies. In particular, IPTV is the largest one of communication/broadcast convergence services. IPTV is a technology that combines conventional television (TV), with voice and data technologies, thereby creating various new business models and services that support bidirectionality.
In particular, the IPTV technology provide the same service in different environments by providing services regardless of the types of terminals (e.g., stationary terminals such as personal computers (PCs) and TVs, and mobile terminals such as Personal Digital Assistants (PDAs)) and the types of networks (e.g., wired/wireless networks and broadcast networks) instead of providing specified services in the conventional limited terminal environments, and can create various services by considering the different environments.
FIG. 1 is a diagram illustrating a value chain of IPTV defined in Open IPTV Forum.
Referring to FIG. 1, IPTV service domains for providing IPTV to a service user 1100 are generally classified into five domains: a consumer domain 1101, a network provider domain 1102, a platform provider domain 1103, an IPTV service provider domain 1104, and a contents provider domain 1105.
The consumer domain 1101 consumes an IPTV service, and may include a terminal for receiving/using a service and a network (e.g., a home network) including a plurality of terminals. Examples of the terminal include settop boxes and portable terminals supporting wireless environments, such as mobile phones and PDAs.
The network provider domain 1102 connects the user 1100 and a platform or a service provider and provides various services and contents. A transmission system of the network provider domain 1102 may support various transmission technologies such as wired/wireless and broadcast technologies and generally includes an access network and a core or backbone network.
The platform provider domain 1103 provides a common service to IPTV service providers, e.g., user authentication and charging.
The IPTV service provider domain 1104 provides IPTV services to the consumer domain 1101. The IPTV service provider domain 1104 receives contents from contents providers and provides a service package thereof.
The contents provider domain 1105 owns contents, contents properties, and contents copyrights.
Scheduled content services, content on-demand services, and various IPTV services can be provided in the aforesaid five domains, and four types of functions of the services form one value chain.
A content production unit 1109 is located in the contents provider domains 1105 to produce and edit contents. The content aggregation unit 1108 is located in the IPTV service provider domain 1104, and receives contents from various content providers to create various services. The content delivery unit 1107 is located in the platform provider domain 1103 and the network provider domain 1102 to deliver services received from IPTV service providers (i.e., aggregated contents) to the consumer domain 1101. The content reconstitution unit 1106 is located in the consumer domain 1101 to convert the received contents into a format viewable by the user 1100.
The IPTV services are classified into a managed model and an unmanaged model (in an open Internet) according to provisions of Quality of Service (QoS).
The managed model is an integrated model in which a service provider manages the platform provider domain 1103, the network provider domain 1102, and the IPTV service provider domain 1104 in an integrated manner. The unmanaged model is a divided model in which a service provider is included in the IPTV service provider domain 1104 and other network providers (the network provider domain 1102 and the platform provider domain 1103) perform transmission.
In general, a home network includes an IP-based private network. The home network connects and controls various devices such as wireless devices, intelligent products such as electronic appliances that can communicate with other devices for configuring the electronic appliances, and PCs, through a virtual computing environment commonly referred to as middleware.
The middleware connects various digital devices in a peer-to-peer manner in order to provide communication between the devices. For example, middleware includes Home AV Interoperability (HAVI), Universal Plug and Play (UPnP), Java Intelligent Network Infra-structure (Jini), Home Wide Web (HWW). In particular, the UPnP network includes UPnP devices and UPnP services and operates according to the protocol therebetween.
The UPnP network includes: Controlled Devices (CDs) connected to an IP-based home network; and a Control Point (CP) for controlling the CDs.
The CP controls a CD, and requests/receives an event. The CD performs a function according to the request of the CP, and transmits an event to the CP requesting the event, if the state of the CD changes.
A UPnP audio/video (AV) technology enabling a user to enjoy multimedia contents, such as audio and video contents using UPnP technology is described in the UPnP AV standard.
FIG. 2 is a diagram illustrating a conventional UPnP AV architecture.
Referring to FIG. 2, according to the UPnP AV standard, a first AV device 20 is a media server that retains AV contents and stores, for example, various image files or audio/video files through a Content Directory Service (CDS). Herein, the CDS is installed in the media server 20 to provide metadata of contents, which are stored in the media server 20 or present in or outside a home network, to an AV Contents Provider (AVCP) 10.
Examples of the media server 20 include a settop box, a Digital Video Disc (DVD) player, an MP3 player, a Digital Still Camera (DSC), and a PC that includes a Hard Disk Drive (HDD), a flash memory, and an optical device such as a DVD or a Compact Disc (CD).
A second AV device 30 is a media rendering device that enables a user to enjoy AV contents. For example, the second AV device includes a Digital TV (DTV), a High Fidelity (HiFi) audio receiver, and a monitor. AV contents are received from the second AV device 20 through an Out-of-Band transmission protocol.
FIG. 3 is a flow diagram illustrating a conventional process for sharing a bookmark between home devices through the conventional UPnP.
Referring to FIG. 3, a user creates a bookmark of contents through a control point 10 (step 11) and stores the created bookmark in a media server 20 (step 12). Thereafter, when the control point 10 is used to give a reproduction command from a bookmark point of the contents (step 13), a media renderer 30 executes the contents with reference to a Uniform Resource Identifier (URI) of the contents and a bookmark start point from the media server 20.
Using the process illustrated in FIG. 3, several media renders 30 can share bookmarks stored in the media server 20.
While there are schemes for representing bookmark information of home contents created by users as UPnP objects, and mechanisms for creating/changing/deleting objects in an UPnP content directory service, there is no technique for using the bookmark created by the user in home devices of other users.
Table 1 below shows an example of a conventional UPnP bookmark. The title of contents is “Gone with the Wind”, an object Identifier (ID) referred to by the bookmark is 1230131, and the time information of the bookmark indicates a point of 00:22:01 from the start point.
TABLE 1<?xml version=“1.0” encoding=“UTF-8”?><DIDL-Litexmlns:dc=“http://purl.org/dc/elements/1.1/”xmlns=“urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/”xmlns:upnp=“urn:schemas-upnp-org:metadata-1-0/upnp/”xmlns:xsi=“http://www.w3.org/2001/XMLSchema-instance”xsi:schemaLocation=“urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/http://www.upnp.org/schemas/av/didl-lite.xsdurn:schemas-upnp-org:metadata-1-0/upnp/http://www.upnp.org/schemas/av/upnp.xsd”><item id=“bookmark-763215” parentID=“BC_001”restricted=“0”><dc:title>Gone with the Wind</dc:title><upnp:class>object.item.bookmarkItem</upnp:class><upnp:deviceUDN serviceType=“AVTransport:1”serviceId=“AVTransport”>uuid:2F5A2466-55EF-44af-953A-74DE96FF2B14</upnp:deviceUDN><upnp:deviceUDN serviceType=“RenderingControl:1”serviceId=“RenderingControl”>uuid:EF0DB408-3018-4e13-831A-8349CA543538</upnp:deviceUDN><upnp:bookmarkedObjectID>1230131</upnp:bookmarkedObjectID><dc:date>2003-03-21T15:21:22</dc:date><upnp:stateVariableCollection serviceName=“AVTransport”><!--The following stateVariableValuePairs XML Document needs to beinterpreted as a simple string and therefore needs to be properly escaped-->&lt;?xml version=“1.0” encoding=“UTF-8”?&gt;&lt;stateVariableValuePairsxmlns=“urn:schemas-upnp-org:av:avs”xmlns:xsi=“http://www.w3.org/2001/XMLSchema-instance”xsi:schemaLocation=“urn:schemas-upnp-org:av:avshttp://www.upnp.org/schemas/av/avs.xsd”&gt;&lt;stateVariable variableName=“RelativeTimePosition”&gt;00:22:01&lt;stateVariable&gt;&lt;!-- More state variable value pairs canbe inserted here --&gt;&lt;/stateVariableValuePairs&gt;<!-- End of stateVariableValuePairs XML Document --></item>